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Publication numberUS7018449 B2
Publication typeGrant
Application numberUS 10/866,250
Publication dateMar 28, 2006
Filing dateJun 14, 2004
Priority dateMar 1, 2001
Fee statusPaid
Also published asEP1363718A2, US6814783, US7115160, US20040011203, US20050002833, US20050016376, WO2002070105A2, WO2002070105A3
Publication number10866250, 866250, US 7018449 B2, US 7018449B2, US-B2-7018449, US7018449 B2, US7018449B2
InventorsThomas M. Fitch, Majid Entezarian, James R. Johnson
Original AssigneePhillips Plastic Corporation
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Filtration media
US 7018449 B2
Abstract
Particles may be used to filter oleo material such as grease from a flow of fluid such as a gas. The particles can be arranged into a bed to filter the oleo material from the fluid. The filtrate substance collect on the inorganic particles. The particles are re-usable, in that they can be subjected to filtrate-separation techniques, e.g., solvent extraction, detergent washing, and centrifugal separation, to separate the oleo material from the particles.
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Claims(57)
1. A method comprising:
(a) filtering grease from an air stream using a bed of porous particles, the air stream being channeled from an area where the grease is being heated to another location by a ventilation system, wherein the particles have a mean pore size of about 0.1 microns to 10 microns,
(b) removing the bed from its position in the air stream;
(c) separating the grease from the particles using a liquid.
2. The method according to claim 1 comprising:
(d) moving the bed back into the air stream.
3. The method according to claim 2 comprising repeatedly performing steps (a)–(d).
4. The method according to claim 1 wherein the grease is separated from the particles using a process comprising solvent extraction, detergent washing, or a combination thereof.
5. The method according to claim 1 wherein the ventilation system channels the air stream from a housing, through a duct, and into the atmosphere.
6. The method according to claim 1 wherein the air stream and the grease form an aerosol.
7. The method according to claim 1 wherein a mean size of the particles is about 0.25 mm to 4 mm.
8. The method according to claim 1 wherein the particles absorb the grease.
9. The method according to claim 1 wherein the particles are inorganic.
10. The method according to claim 1 wherein the particles comprise metal, ceramic material, or a combination thereof.
11. A method comprising:
filtering grease from an air stream using a bed of particles, the air stream being channeled from an area where the grease is being heated to another location by a ventilation system;
cyclically separating the grease from the particles using a liquid;
wherein a mean size of the particles is about 0.1 mm to 4 mm.
12. The method according to claim 11 comprising removing the bed from its position in the air stream to separate the grease from the particles.
13. The method according to claim 11 wherein the grease is separated from the particles using a process comprising solvent extraction, detergent washing, or a combination thereof.
14. The method according to claim 11 wherein the ventilation system channels the air stream from a housing, through a duct, and into the atmosphere.
15. The method according to claim 11 wherein the air stream and the grease form an aerosol.
16. The method according to claim 11 wherein the particles are porous.
17. The method according to claim 11 wherein the particles absorb the grease.
18. The method according to claim 11 wherein the particles are inorganic.
19. The method according to claim 11 wherein the particles comprise metal, ceramic material, or a combination thereof.
20. A ventilation system comprising:
a bed of porous particles which is used to remove grease from an air stream where the grease is from heating food, the particles being regenerated using a liquid;
wherein the ventilation system channels the air stream from a housing through a duct and into the atmosphere; and
wherein a mean size of the particles is about 0.25 mm to 4 mm.
21. The ventilation system according to claim 20 wherein the particles are regenerated using detergent washing.
22. The ventilation system according to claim 20 wherein the particles are cyclically regenerated.
23. The ventilation system according to claim 20 wherein the particles are inorganic.
24. The ventilation system according to claim 20 wherein the air stream and the grease form an aerosol.
25. The ventilation system according to claim 20 wherein the particles absorb the grease.
26. The ventilation system according to claim 20 wherein the particles comprise metal, ceramic material, or a combination thereof.
27. A ventilation system comprising:
a bed of porous particles which is used to remove grease from an air stream where the grease is from heating food, the particles being cyclically regenerated using a liquid, the particles also having a mean pore size of about 0.1 microns to 100 microns;
wherein the ventilation system channels the air stream from an area where the grease is being heated to another location.
28. The ventilation system according to claim 27 wherein the particles are regenerated using a process comprising solvent extraction, detergent washing, or a combination thereof.
29. The ventilation system according to claim 27 wherein the ventilation system channels the air stream from a housing, through a duct, and into the atmosphere.
30. The ventilation system according to claim 27 wherein the air stream and the grease form an aerosol.
31. The ventilation system according to claim 27 wherein a mean size of the particles is about 0.1 mm to 4 mm.
32. The ventilation system according to claim 27 wherein the particles are inorganic.
33. The ventilation system according to claim 27 wherein the particles absorb the grease.
34. The ventilation system according to claim 27 wherein the particles comprise metal, ceramic material, or a combination thereof.
35. A ventilation system comprising:
a bed of particles which is used to remove grease from an air stream where the grease is from heating food, the particles being cyclically regenerated using a process comprising solvent extraction, detergent washing, or a combination thereof;
wherein the ventilation system channels the air stream from an area where the grease is being heated to another location.
36. The ventilation system according to claim 35 wherein the ventilation system channels the air stream from a housing, through a duct, and into the atmosphere.
37. The ventilation system according to claim 35 wherein the air stream and the grease form an aerosol.
38. The ventilation system according to claim 35 wherein the particles are porous.
39. The ventilation system according to claim 35 wherein the particles are inorganic.
40. The ventilation system according to claim 35 wherein the particles absorb the grease.
41. A filtration media comprising:
a plurality of porous particles arranged in a bed, the bed being configured to be positioned in a ventilation system which channels an air stream from an area where grease is being heated to another location, the bed also being configured to remove the grease from the air stream;
wherein the bed is regenerated using a process comprising solvent extraction, detergent washing, or a combination thereof.
42. The filtration media according to claim 41 wherein the particles are cyclically regenerated.
43. The filtration media according to claim 41 wherein the particles are inorganic.
44. The filtration media according to claim 41 wherein the particles are configured to absorb the grease.
45. The filtration media according to claim 41 wherein the particles comprise metal, ceramic material, or a combination thereof.
46. The filtration media according to claim 41 wherein the ventilation system channels the air stream from a housing, through a duct, and into the atmosphere.
47. A method comprising:
(a) filtering grease from an air stream using a bed of porous inorganic particles, the air stream being channeled from an area where the grease is being heated to another location by a ventilation system, wherein a mean size of the particles is about 0.1 mm to 4 mm and the particles have a mean pore size of about 0.1 microns to 100 microns.
(b) removing the bed from its position in the air stream;
(c) separating the grease from the particles using a liquid.
48. The method according to claim 47 wherein the mean size of the particles is about 0.25 mm to 4 mm and the mean pore size is about 0.1 microns to 10 microns.
49. The method according to claim 47 wherein the grease is separated from the particles using a process comprising solvent extraction, detergent washing, or a combination thereof.
50. The method according to claim 47 wherein each of the porous inorganic particles has interconnecting openings extending throughout the particle and opening onto an outer surface of the particle to form a reticulated labyrinth of struts.
51. A method comprising:
filtering grease from an air stream using a bed of porous inorganic particles, the air stream being channeled from an area where the grease is being heated to another location by a ventilation system; and
cyclically separating the grease from the particles using a liquid;
wherein a mean size of the particles is about 0.1 mm to 4 mm; and
wherein the particles have a mean pore size of about 0.1 microns to 100 microns.
52. The method according to claim 51 wherein the mean size of the particles is about 0.25 mm to 4 mm and the mean pore size is about 0.1 microns to 10 microns.
53. The method according to claim 51 wherein the grease is separated from the particles using a process comprising solvent extraction, detergent washing, or a combination thereof.
54. The method according to claim 51 wherein each of the porous inorganic particles has interconnecting openings extending throughout the particle and opening onto an outer surface of the particle to form a reticulated labyrinth of struts.
55. A method comprising:
(a) filtering grease from an air stream using a bed of porous inorganic particles, the air stream being channeled from an area where the grease is being heated to another location by a ventilation system, wherein each of the porous inorganic particles has interconnecting openings extending throughout the particle and opening onto an outer surface of the particle to form a reticulated labyrinth of struts,
(b) removing the bed from its position in the air stream;
(c) separating the grease from the particles using a liquid.
56. The method according to claim 55 wherein the mean size of the particles is about 0.1 mm to 4 mm and the mean pore size is about 0.1 microns to 100 microns.
57. The method according to claim 55 wherein the mean size of the particles is about 0.25 mm to 4 mm and the mean pore size is about 0.1 microns to 10 microns.
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a continuation of: U.S. patent application No. 10/363,849, entitled “Filtration Media of Porous Inorganic Particles,” filed on Mar. 14, 2003 now U.S. Pat. No. 6,814,783, pending, which is the National Stage of International Application No. PCT/US02/05753, entitled “Filtration Media of Porous Inorganic Particles,” filed on Feb. 28, 2002, published in English, which: (1) claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application No. 60/272,044, entitled “Filtration Media of Porous Inorganic Particles,” filed on Mar. 1, 2001, and (2) claims the benefit under 35 U.S.C. § 365(c) of U.S. patent application No. 10/076,144, entitled “Filtration Media of Porous Inorganic Particles,” filed on Feb. 15, 2002, abandoned, which also claims the benefit of U.S. Provisional Application No. 60/272,044, entitled “Filtration Media of Porous Inorganic Particles,” filed on Mar. 1, 2001 all of which are hereby expressly incorporated by reference herein in their entireties.

FIELD OF THE INVENTION

The invention relates generally to filtration. More specifically, the invention relates to the use of porous inorganic particles in a filtration apparatus, such as a packed bed, where the apparatus includes porous, inorganic particles. The invention also contemplates the use of the porous, inorganic particles, particularly in a packed bed, which are capable of filtering one or more substances from a fluid, such as air.

BACKGROUND OF THE INVENTION

Filtration media can be used to prevent undesirable vapors, particulate, or suspended droplets in a gas stream from escaping into the atmosphere. For example, whenever an oleo material or substances (e.g. grease, oil or fat) are heated, some will vaporize or form droplets. There is a desire to prevent such vaporized or droplet material from escaping into the air, unfiltered. Presently employed filtering media can include an aggregate of fibrous material, such as organic fiber mat or inorganic fiberglass, that extend over the traveling path of a vapor or liquid, such that the fibrous material catches the oleo vapors or droplets as they pass through the interstices of the filtering material. Although, initially, such filtering mechanisms may be capable of efficiently removing the oleo vapors or droplets from the air stream, the oleo vapors or droplets gather in the interstices of the filtering material in increasing quantities as the filtration process progresses, resisting the flow.

The flow rate of air through the filter immediately begins to decrease as the oleo material begins to collect on the filter media. This build-up of undesirable substances can substantially or completely block the flow of air and its load of material to be filtered through the filter, requiring frequent replacement of the filter. This replacement process typically requires a shut down of the mechanism that produces the vapor. Often times, the filter, upon having the undesirable substance collected thereon is disposed of without further use.

U.S. Pat. No. 5,776,354, issued to van der Meer et al., discloses a method for separating a dispersed liquid phase (i.e. an oil film) from a gas, using a filter bed of a particulate, porous polymer material whose size is on the order of 0.1 to 10 mm. Although van der Meer et al. teach that the dispersed liquid phase can fill into the pores of the particulate material, the particulate material is a polymer, thereby restricting the available methods for subsequently separating the liquid phase from the particulate material. In fact, van der Meer et al. only teach centrifugal force (i.e. a centrifuge) for separating the oil from particulate material. Thus, there remains need for filtration media that not only (1) ameliorate the problem of restricted airflow through the filter, but (2) also can undergo harsher filtrate-separation processes, yet subsequently retain its desired properties for repeated use.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the invention to provide renewable, porous filtering media to separate a filtrate substance (in the form of vapor, aerosol, and/or liquid) from a fluid such as a gas or liquid, such that the flow of the fluid through the porous filtering media will not be substantially impeded prior to the time said porous media are filled with said vapor, aerosol, and/or liquid.

It is a further object of the invention to provide filtering media that can retain their filtering properties subsequent to undergoing a harsh filtrate-separation protocol.

It is another object of the invention to provide filtering media that permit a continuous, uninterrupted fluid flow. This provides a uniform filtration mode until the media are saturated.

The invention provides for a filtration media that includes porous particles (whose composition is inorganic) arranged to separate one or more filtrate substances from a fluid or fluids wherein the porous particles collect and retain within themselves the filtrate substance(s). In a preferred embodiment, the porous particles are arranged in a packed bed. In a particularly preferred embodiment, the particles relinquish substantially all of the substances during a separation step and the particles maintain the ability to collect the substance(s) repeatedly.

The invention further contemplates an apparatus for separating one or more substances from a moving fluid which includes a housing for said packed bed of porous particles located in a duct through which said moving fluid with the filtrate substance(s) is passing. Various designs may be used so as to cycle the moving fluid through a plurality of such housings and beds without having to shut down the system. Further, the beds may be treated in said cycles so as to refresh the particles for their intended use.

In a preferred embodiment, the invention describes a method for substantially separating one or more oleo substance(s) from a fluid, particularly a gas such as air, which comprises the steps of placing the inorganic, porous particles, which may be spherical or pellet-like in shape or have other shapes, into contact with the fluid, which moves relative to the particles; and allowing the oleo substance(s) to collect within at least a portion of the inorganic particles as the vapor composition passes at least substantially through the inorganic porous particles. In one sense, the inorganic porous particles are arranged to form a network, such as a packed bed, suitable for filtering the oleo substance(s) from the moving fluid.

Methods according to the invention further comprise substantially separating the filtrate substance from the inorganic, porous particles and repeating the steps of placing the inorganic, porous particles into contact with the fluid and allowing the filtrate substance to collect within at least a portion of the inorganic particles.

In another embodiment, the filtrate substance includes hydrophilic vapors or suspended droplets. This invention provides a method for substantially separating the hydrophilic vapors or suspended droplets by placing the inorganic, porous particles, preferably in the form of a packed bed, into contact with a fluid flow which contains the filtrate substance. This allows the hydrophilic substance to collect within at least a portion of the inorganic particles due to the hydrophilic nature of internal and external surfaces of the porous particles. Further, the internal surfaces of the pores of said particles may be treated with reactive substances that may be biocidal, catalytic, or chemically reactive with the contents of said vapors or suspended droplets.

These and other objects will be apparent to a skilled worker, as shown by the embodiments described and contemplated herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a filtration apparatus comprising a packed bed of inorganic particles and a ventilation system according to one embodiment of the present invention.

FIGS. 2A–2D show a filtration apparatus comprising a packed bed of inorganic particles and a ventilation system according to another embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides, inter alia, inorganic, porous particles that are capable of trapping filtrate substances from a fluid. As used herein, “filtrate substance” is defined as the substance (e.g., gas, vapor, liquid, suspended droplets, etc.) that is intended to be removed from the fluid. The fluid containing the filtrate substance can be either a gas or liquid.

The particles are suitable for separating one or more of the filtrate substances from a fluid flow, e.g. a gas, which contains such filtrate substances. To this end, in a preferred embodiment, the inorganic particles can be arranged into a packed bed-like formation, or network, such that the network comprises (1) particles interacting with each other and (2) interstices defined between the exterior surface area of the interacting particles. Thus, in one embodiment, a fluid containing the filtrate substances can flow through (or substantially through) the packed bed, leaving behind one or more filtrate substances that collect within at least a portion of the particles. Although the embodiments described herein indicate that the fluid moves relative to the filter media, other embodiments such as those in which the filter media move are also contemplated.

A particularly preferred combination is one in which the filtrate substance is a grease, fat or oil (collectively referred to as an “oleo substance”) and the fluid is air.

As indicated, the inorganic particles, or media, that comprise the core of the filtration apparatus described more fully below, are porous, having an external surface area and a network of open channels that define internal surfaces. In a preferred embodiment, the inorganic particles can have any suitable shape, e.g., spherical, pellet-like, etc. The particles may have any suitable size depending on end use, and may range in size from about 0.25–4 mm, preferably 0.33–3.5 mm, and more preferably 0.5–3 mm. For non-spherical particles, the size measurement is taken at the largest dimension. In other suitable embodiments, the particles can have a size that ranges from greater than 4 mm, preferably from greater than 4 to 50 or even 100 mm. In some embodiments, the pores preferably have a mean size between about 0.01 to 100 microns, preferably 0.1 to 10 microns. The media can also have other shapes such as porous fibers and other formed shapes such as rings, saddles, etc.

The inorganic particles can have porosity in the range of 15–70%, preferably 30–70%. These internal surfaces accordingly are exposed to the filtrate substance (e.g. oleo) substance(s) passing through the network of particles. That is, the pores of the inorganic particle or particles are large enough such that the filtrate substance can fit inside of, or otherwise pass through, one or more pores. Accordingly, in one embodiment, the surfaces of the pores can comprise an oleophilic substance and, therefore, attract an oleo substance. In this sense, a relatively powerful force, such as surface tension, can draw the filtrate substance within the openings of the pores. Hence, the filtrate substance, such as an oleo substance, can collect within the pores in lieu of and/or in addition to adhering to the exterior surface area of the particles. In other embodiments, described more fully below, the interior and/or exterior of the particle can have a catalyst and/or reactant coated thereon.

The open channels, e.g., pores, of the inorganic particle in a preferred embodiment can exist in a reticulated, open, sintered structure. In this sense, a reticulated structure is a structure made up of a network of interconnected struts that form a strong, interconnected continuum of pores. A method for preparing a sinterable structure is disclosed in co-pending application Ser. No. 09/286,919, entitled “Sinterable Structures and Method”, which is hereby incorporated herein by reference in its entirety. More specifically, this co-pending application describes processes for producing a porous, sintered structure, comprising (1) preparing a viscous mixture comprising a sinterable powder of ceramic or metal dispersed in a sol of a polymer in a primary solvent; (2) replacing the primary solvent with a secondary liquid in which the polymer is insoluble, thereby producing a gel which comprises an open polymeric network that has the sinterable powder arranged therein; (3) removing the secondary liquid from the gel; and (4) sintering the sinterable powder to form the open, porous structure.

The particles of the invention may be comprised of any inorganic material that confers the requisite characteristics upon the particles (e.g. capable of containing pores, at least substantially maintains porosity and ability to collect a filtrate substance inside the pores of the particles after a filtrate-separation operation described more fully below, preferably a harsh filtrate separation). An illustrative list of suitable materials of which the particles can be comprised include: a ceramic material such as transition metal oxides, zircon, zirconia, titania, silica, alumina, alumina-silica (clay) or a variable blend thereof. An especially preferred particle is a clay such as kaolin, bentonite or montmorillonite. Porous iron made by 09/286,919 also will absorb oleo substances.

The individual porous particles, once formed, can be assembled into a network suitable for filtering the one or more substances from the fluid composition. The porous particles can be arranged as a packed bed in a vertical plane, a horizontal plane or both. Preferably, each porous particle interacts with at least one other particle, yet forms interstices between the particles, such that a fluid can pass through the interstices. In one embodiment, the porous particles form a bed that defines a constant surface area. Three particles preferably extend along at least the horizontal or vertical cross section of the bed or casing to define a continuous section of alternating particles and interstices. An example is a bed of porous particles packed within a perforated or porous wall container. Alternatively, two or more particles of the bed may be physically attached, such as by heating the particles to sufficient temperature to sinter the particles together, while maintaining space between the particles sufficient to allow the passage of a vapor or liquid therethrough.

Once formed, the inorganic porous particles, which can be in the form of the network described above, can be placed into contact with a fluid composition containing the filtrate substance, preferably an oleo substance. The particles may be positioned in association with a fluid such that the fluid passes through or at least substantially through the interstices and/or pores of inorganic particles, leaving behind at least a portion, but preferably the majority, of the filtrate substance suspended in the fluid. In this sense, the filtrate substance collects on and within the inorganic particles.

As the fluid passes through the packed bed of inorganic particles, there is resistance to the flow, resulting in a drop in pressure on the exit side of the bed. In a preferred embodiment, this drop in pressure remains substantially constant, which means that the filtrate substance collects within the pores to a greater extent than in the interstices between the exterior surface area of the particles. At any time, the inorganic particles can be removed from the flow of fluid, in order to separate the filtrate substance from inorganic particles. In some embodiments, the particles may be regenerated, in situ. However, it is preferred that the particles are removed from the fluid flow whenever the filtrate substance at least substantially has filled the pores and/or may have begun to fill the interstices between the inorganic particles. This conveniently can be determined by detecting a measurable decrease in the pressure of the fluid through the filter media.

The inorganic particles may be removed from the fluid flow in any number of ways, from simple replacement to automated systems. For instance, the particles can be a magnetic material and an external magnetic force may be applied to draw the particles away from the fluid flow, such as vapor flow. Alternatively, gravitational forces could be employed to move the particles downwardly, for example, beneath the fluid flow. In addition, a vacuum force could be used to pull the particles out of the stream of flowing fluid. Further still, the invention contemplates the employment of a see-saw apparatus that has the filter media on both ends of a pivoting elongated member, where the media can be raised and lowered from a filtering position to a regeneration position. In a similar manner, a rotating wheel or disk containing the filtering media can be rotated from a position of filtering to a position of separation and/or regeneration.

The separation step preferably is carried out such that, upon removing the filtrate substance from the inorganic materials, the inorganic particles again can be used to filter a substance from a moving stream of fluid as before. Filtrate-separation operations may be selected from the group consisting of heat treatment at a temperature sufficient to volatilize the filtrate substances and burn off any remaining residue (up to 1000° C.), solvent extraction, detergent wash, and centrifugal removal, and combinations of these separations. Particularly preferred separation operations are harsh filtrate separations such as heat treatment and solvent extraction. Suitable solvents for removing the filtrate substance may include organic solvents or preferably known biodegradable solvents. A detergent suitable for the detergent washing step can be a commercial one, e.g., DAWN. Other known suitable detergents can also be used. A significant advantage of the present invention is that the inorganic porous particles are capable of withstanding harsh separation treatments where necessary as described above. After the filtrate substance is removed from the inorganic particles, the filtrate substance may be discarded and the particles can be re-positioned within the stream of the flowing fluid. The filtrate collection and separation process can be repeated multiple times.

In the catalytic embodiment, described below, the separation step can be facilitated by incorporation of the catalyst. Because the internal pores are completely available in the sintered structure of 09/285,919, a catalyst coated on the pore walls substantially increases the catalyst availability to reactants, e.g. hydrocarbons and oxygen.

In another embodiment, for instance, porous particles of the invention could contain hydrophilic surfaces within the porous area. The invention, accordingly, contemplates the removal of malodorous or toxic vapors from air. Current filtration apparatus in air conditioning systems, for example, might not effectively remove harmful vapors or droplets, such as those carrying spores or bacteria, e.g. the so-called “Legionnaire's Disease.” A porous filter, as described herein, having surfaces adapted to be hydrophilic, could capture noxious vapors or droplets. Thereafter, the trapped vapors or droplets could be heated, thereby destroying any bacteria, spores, virus or other harmful material associated with the vapors or droplets. In a preferred embodiment, the surfaces of the pores, such as struts, can be coated or impregnated with a biocidal agent, such as well known silver containing biocides, e.g., silver iodide and/or antibiotics, e.g., tetracycline. Another possible coating could include diazeniumdiolate in a siloxane polymer. Of course, the exterior surface of the porous particles can also be coated or impregnated with a biocidal agent.

In still another embodiment, the filtrate substance is treated and subsequently removed by reacting the filtrate substance using a catalyst that is within the pores and on the exterior surface of the particles. Optionally, the filtrate substance can be reacted with another component that may be coated on the particle, in the fluid, or even the fluid itself. In one embodiment, ethane can be reacted in and subsequently removed from a gas stream by converting the ethane to ethylene in the presence of hydrogen using a noble metal catalyst on the surface and within the pores of the particles. This catalytic reaction can occur by passing the fluid over or through a bed of the inorganic particles, or within a fluidized bed of the same particles.

The invention also provides an apparatus for substantially separating one or more filtrate substances from a moving fluid stream. This apparatus may comprise a packed bed or network of inorganic particles, as described, in combination with a series of vents or ducts that channel the fluid stream towards the network of inorganic particles. The system also may comprise a series of vents or ducts that channel the fluid to another location, upon passing through the network of inorganic particles. For instance, the fluid may exit into the atmosphere upon passing through the inorganic particles. Alternatively, the fluid first may pass through a catalyst bed for further treatment of the fluid.

The system can be constructed such that the source creating the fluid flow does not need to be turned off in order to perform the filtrate substance removing step. To this end, the system may comprise multiple series of ducts or vents that can be operated in tandem with each other. Accordingly, one series of ducts or vents may be opened, while the others are closed. The open series would act to direct the fluid, such as a vapor, to the inorganic particles and then away from the particles after passing therethrough. At the appropriate time, the inorganic particles, having the filtrate substance collected therein, can be cleaned by a filtrate-separation protocol, for example. Further, the inorganic particles may remain substantially at their present location or they may be moved to a different location (e.g. by magnetic, vacuum or gravitational force) before separating the filtrate substance(s) from the particles. At this stage, the open series of vents or ducts can be closed and the closed series then can be opened, as the filtering process continues.

One non-limiting example of a filtration apparatus contemplated by the invention is described in the schematic diagram of FIG. 1. With reference to FIG. 1, housing (1) holds the filtrate substance, e.g., an oleo substance. Upon being heated within the housing, the filtrate substance in a fluid (in this instance in a stream of flowing exhaust air) enters duct (2). The filtrate substance can then be selectively passed into duct (3) or (4), such as by a valve. The filtrate substance enters the filter media (5) or (6), that includes the network of inorganic particles. A pre-filter (not shown) may be positioned before the filter media.

The filtrate substance collects within interstices and pores of the particles (not shown), as the exhaust passes through the filter media. Thereafter, the exhaust passes into and through ducts (7) or (8) which lead to catalytic reactor (9). After passing through catalytic reactor (9), the exhaust can be vented into the atmosphere (10).

The filter media can be positioned adjacent to electric heater (not shown), that, when activated, can transfer heat to particles in the filter media. The heat will cause the filtrate substance, such as an oleo substance (not pictured) to separate from the particles that can be drained as needed. Generally, the heat-separation process occurs when the apparatus is shut down, or when the fluid flow directed into the other filter media.

Another embodiment is shown in connection with FIGS. 2A–2D. With reference to FIG. 2A, housing (11) holds the filtrate substance, e.g., an oleo substance. Upon being heated within the housing, the filtrate substance enters duct (12). The filtrate substance then enters into filter media (16). FIG. 2D shows the cross section of filter media 16 taken along line I—I. In an embodiment shown in FIG. 2B, the filtrate substance can then be selectively passed into duct (14) or (15), such as by a valve (13), and then enter the filter media (16) or (17), that includes the network of inorganic particles. A pre-filter (not shown) may be positioned before the filter media.

Thereafter, in the embodiment of FIGS. 2A and 2B, the exhaust gas passes into fan (18) and is vented into the atmosphere through vent (19). In the embodiment shown in FIG. 2C, the exhaust first passes into catalytic reactor (20) before passing into fan (18).

Additional advantages, features and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices, shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

As used herein and in the following claims, articles such as “the,” “a” and “an” can connote the singular or plural. All documents referred to herein are specifically incorporated herein by reference in their entireties.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US768415Feb 8, 1904Aug 23, 1904Thomas R WingroveOil-intercepter.
US1743675Mar 10, 1923Jan 14, 1930Jordahl AndersAir filter
US1872892Jun 6, 1930Aug 23, 1932Paul KramerMechanical sand washer
US1926924Apr 30, 1928Sep 12, 1933American Air Filter CoSinuous air filter and medium
US2621755Apr 20, 1948Dec 16, 1952Gray Jr Dallas HAir-filter machine
US2633929Aug 24, 1948Apr 7, 1953Farr CoApparatus for filtering air
US2641331Mar 20, 1950Jun 9, 1953Hudson Harold LFlue for deep-frying equipment
US2794514Jan 18, 1956Jun 4, 1957Douglas S RisleySmoke hood with filter unit for cooking stove
US2886124Jul 13, 1956May 12, 1959Duct Less Hood Co IncKitchen conditioner
US2978064Feb 19, 1959Apr 4, 1961Do More Products CorpGas purifier
US3049399Dec 18, 1958Aug 14, 1962Borg WarnerComposition and method for deodorizing air
US3354623Sep 27, 1965Nov 28, 1967American Air Filter CoUnit filter assembly
US3433146Nov 30, 1966Mar 18, 1969Kenneth Sinclair RussellGrease extracting ventilating apparatus
US3674683Jan 2, 1970Jul 4, 1972Philip Morris IncProcess for the removal of oil from the surface of a body of water
US3785124Aug 2, 1971Jan 15, 1974Gaylord IndPollution-free kitchen ventilator
US3837269Nov 22, 1972Sep 24, 1974Elster S IncEffluent ventilation and cleaning apparatus
US3854912Sep 11, 1972Dec 17, 1974Lau Prod LtdCombined grease trap and air filter for range hoods
US3955949Oct 15, 1974May 11, 1976Smith Filter CorporationExhaust systems
US3970558Feb 21, 1974Jul 20, 1976Kai Sing LeeFrying grease reclaimer
US4022118Apr 12, 1976May 10, 1977Mcgraw-Edison CompanyKitchen ventilator grease extractor construction
US4042352Apr 22, 1976Aug 16, 1977Sumitomo Chemical Company, LimitedFixed packed beds
US4082661Jul 29, 1975Apr 4, 1978Sumitomo Durez Company, Ltd.Impregnation of porous ceramic filter with phenolic resin followed by carbonization
US4104163Feb 24, 1977Aug 1, 1978Standard Oil Company A Corporation Of IndianaSodium hydroxide solution
US4105422Jan 31, 1977Aug 8, 1978Kikuchi Kogyo Kabushiki KaishaFiltration device
US4118206Dec 7, 1976Oct 3, 1978Fisher-Klosterman, Inc.Oil mist filtering apparatus and method
US4126433Oct 12, 1976Nov 21, 1978Forssberg Knut S EMethod of and apparatus for removing aerosols of hydrocarbons from a gas stream
US4154812Mar 25, 1977May 15, 1979W. R. Grace & Co.Precipitation from aluminum sulfate and sodium aluminate
US4172031Nov 4, 1975Oct 23, 1979The Dow Chemical CompanySeparation of oil from water
US4177142Sep 27, 1977Dec 4, 1979Ecodyne CorporationMixture of oppositely charged filter aid material
US4231768Sep 29, 1978Nov 4, 1980Pall CorporationAir purification system and process
US4235200Feb 26, 1979Nov 25, 1980Shay Michael AAutomatic animal feeder
US4238334Sep 17, 1979Dec 9, 1980Ecodyne CorporationPurification of liquids with treated filter aid material and active particulate material
US4292285Dec 10, 1979Sep 29, 1981Taiyo Kaken Company, Ltd.Method for removing compounds with offensive odor from a gas containing the same
US4319898Mar 20, 1981Mar 16, 1982Air Filter CorporationAir cleaner
US4328105Feb 6, 1980May 4, 1982Linde AktiengesellschaftFiltration on polyurethane beds
US4350504Jan 28, 1980Sep 21, 1982Century 21 Pollution Control, Inc.Air cleaning system
US4388086Aug 28, 1981Jun 14, 1983Bauer-Kompressoren GmbhThree stage-dehumidification, oil adsorption, dehumidification
US4484563Oct 11, 1983Nov 27, 1984Alco Foodservice Equipment CompanyAir ventilation and pollution cleaning system
US4485622Oct 7, 1981Dec 4, 1984Nippon Soken, Inc.Exhaust gas cleaning device for internal combustion engine
US4534775Apr 19, 1984Aug 13, 1985General Time Corp.Air treatment filter element and air treatment filter
US4545792Feb 27, 1984Oct 8, 1985Condair AgDevice and process for precipitating foreign matter from a gas stream
US4595509Aug 9, 1984Jun 17, 1986Aluminum Company Of AmericaPassing water contaminated with PCB's through filter bed of nonporous inorganic particles, hydraulically shearing particles to remove PCB's
US4604110Feb 28, 1985Aug 5, 1986General Time CorporationDry mixture of silica gel, activated carbon, and zeolite
US4610705Nov 6, 1984Sep 9, 1986Broan Manufacturing Co. Inc.Removing noxious gases
US4629479May 14, 1985Dec 16, 1986Ital Idee S.R.L.Multiple filter unit
US4645605Jul 13, 1984Feb 24, 1987Agritec, Inc.Filtration with biogenetic silica
US4682992Jun 25, 1984Jul 28, 1987Potters Industries, Inc.Microbicidal coated beads
US4708000Mar 13, 1987Nov 24, 1987Canadian Gas Research InstituteApparatus for balanced heat recovery ventilation - heating - humidification - dehumidification - cooling and filtration of air
US4721624Oct 25, 1985Jan 26, 1988Fibeg Beteiligungesellschaft MbhProcess for removing harmful residues from food during cooking
US4805525May 29, 1987Feb 21, 1989Bivens Thomas HApparatus for filtering liquids
US4811724Sep 13, 1985Mar 14, 1989Halton OyAir exhausting means
US4816499Jun 24, 1987Mar 28, 1989Director General Of Agency Of Industrial Science And TechnologyPorous inorganic particles modified with amino and carboxyl groups
US4830644Jan 11, 1988May 16, 1989Paul GutermuthSeparator for gaseous fluids
US4854949Apr 19, 1988Aug 8, 1989Giles Enterprises, Inc.Apparatus for cooking food including a ventless exhaust system
US4872892Sep 16, 1988Oct 10, 1989Halton OyAir purifier
US4900341Jun 29, 1988Feb 13, 1990Metatron Investments, Inc.Purification system
US4902316Oct 28, 1988Feb 20, 1990Giles Enterprises, Inc.Oven including a ventless exhaust system
US4908050Aug 15, 1989Mar 13, 1990Tabai Espec Co. Ltd.Oil mist remover
US4921509Aug 26, 1988May 1, 1990Micro-Technology Licensing CorporationAir filtration system for ducted range hoods
US4923725 *Jul 29, 1988May 8, 1990E. I. Du Pont De Nemours And CompanyArticle for absorbing cooking grease
US4944782Feb 6, 1989Jul 31, 1990S. C. Johnson & Son, Inc.Baffle type hood and duct filters for commerical use
US4969936Dec 26, 1989Nov 13, 1990Westates CarbonFiltration apparatus
US4973341Oct 25, 1989Nov 27, 1990Richerson Ben MCyclonic separator for removing and recovering airborne particles
US4976760Sep 8, 1989Dec 11, 1990Cercona, Inc.Open-cell refractory
US5002040Feb 15, 1990Mar 26, 1991Macfarlane GeorgeComplete air package exhaust unit
US5003693Sep 11, 1989Apr 2, 1991Allen-Bradley International LimitedManufacture of electrical circuits
US5022901Apr 27, 1989Jun 11, 1991Her Majesty The Queen In Right Of Canada, As Represented By The Minister Of National DefenceCompression seal canister
US5053064Oct 11, 1990Oct 1, 1991Mitsubishi Denki Kabushiki KaishaAir conditioning apparatus for a clean room
US5087272Oct 17, 1990Feb 11, 1992Nixdorf Richard DFilter and means for regeneration thereof
US5124177Feb 10, 1990Jun 23, 1992D-Mark, Inc.Filter and method of making same
US5133786Jan 26, 1990Jul 28, 1992Anderson Edward MMethod and apparatus for minimizing odor during hot oil food cooking
US5145648Jun 26, 1989Sep 8, 1992Matsushita Electric Industrial Co., Ltd.Exhaust smoke purifier apparatus
US5154743Apr 18, 1991Oct 13, 1992Kuraco LimitedGrease extractor
US5171720Sep 20, 1989Dec 15, 1992Asahi Kogaku Kogyo K.K.Mixing with CMC, entraining air bubbles, gelation, drying, cutting, firing; three-dimensional, high strength network of micro- and macropores; bone prostheses, catalyst supports
US5179061Jul 12, 1991Jan 12, 1993Haerle Hans AFilter or catalyst body
US5209887Feb 25, 1991May 11, 1993Bluecher HubertProcess for manufacturing microspherules of activated carbon
US5211159May 6, 1991May 18, 1993Standex International CorporationExhaust hood with disposable filter assembly and filter-condition sensor
US5251608Jul 22, 1991Oct 12, 1993Cameron CoteAir canopy ventilation system
US5288298Jun 22, 1992Feb 22, 1994Aston William TLayer of fabric bearing porous activated carbon particulate deodorizing agents; layer of foam impregnated with biostat; no need for increased air circulation
US5302354Jun 26, 1992Apr 12, 1994Pall CorporationFiltration device
US5320088Jun 30, 1993Jun 14, 1994Aerolator Systems, Inc.Ventilator assembly and method of removing kitchen exhaust fumes
US5342422Nov 30, 1993Aug 30, 1994Wimbock Besitz GmbhApparatus for separating particles, in particular oil or fat particles
US5384290Dec 16, 1993Jan 24, 1995W. R. Grace & Co.-Conn.Porous ceramic beads
US5404799Jan 26, 1994Apr 11, 1995Bivens; Thomas H.Continuous filtering fryer
US5442924Feb 16, 1994Aug 22, 1995The Dow Chemical CompanyLiquid removal from natural gas
US5472342Dec 27, 1993Dec 5, 1995Ldi, Mfg. Co., Inc.Kitchen exhaust hood grease extractor
US5479907Jul 12, 1994Jan 2, 1996Walker, Jr.; Robert A.Combination in-line air-filter/air-oil separator/air-silencer with preseparator
US5486370Dec 15, 1994Jan 23, 1996Bivens; Thomas H.Method of continuously filtering cooking oil
US5497620Dec 28, 1992Mar 12, 1996Stobbe; PerMixing silicon carbide, binder, and viscosity control agent; extrusing, sintering
US5512088Jun 23, 1994Apr 30, 1996Interglobe Gas Technology, Inc.Filtering device for filtering moisture from a natural gas stream
US5567090Apr 22, 1993Oct 22, 1996Foster Wheeler Energia OyMethod and apparatus for separating solids from gas in a high pressure solids-gas stream utilizing a packed bed of the solids
US5567392Jun 28, 1994Oct 22, 1996Mannesmann AktiengesellschaftDevice for the purification of contaminated exhaust air through heterogeneous catalysis
US5624875Jul 15, 1994Apr 29, 1997Merck Patent Gesellschaft Mit Beschrankter HaftungGlass or glass-ceramic used for chromatography columns, filters for separating blood, porous catalysts, or enzyme supports
US5628916Nov 9, 1995May 13, 1997Pall CorporationMethod for filtering edible oils
US5632889Jun 9, 1995May 27, 1997Tharp; Gary D.Insert for placing in catch basin including cartridge containing absorbent particles which absorb liquid hydrocarbons from water flowing therethrough
US5637124Mar 23, 1995Jun 10, 1997Helical Dynamics, Inc.Modular air cleaning system
US5651803Dec 21, 1995Jul 29, 1997Helical Dynamics, Inc.Modular air-handling system with sealing devices
US5669947Dec 21, 1995Sep 23, 1997Helical Dynamics, Inc.Latch for modular air handling system
US6010558 *Aug 13, 1998Jan 4, 2000Flame Gard, Inc.Grease containment system and method for absorbing grease
USD373625May 19, 1995Sep 10, 1996 Air purifying baffle
USRE34636Dec 24, 1991Jun 14, 1994Bivens Thomas HApparatus for filtering liquids
Non-Patent Citations
Reference
1"Filter som sätter miljön I första rummet", airMet Metal Filter, Luftfilter, obtained from website @ www.luftfilter.com, Feb., 2001, (8 pages).
2"Filter which puts the environment first", airMet Metal Filter, Luftfilter, obtained from website @ www.luftfilter.com, Oct., 2001, (8 pages).
3"Greenheck Takes the Grease Out of Kitchen Ventilation," Dec. 2001, 4 pages.
4"List Prices Effective Jan. 1, 2000, How to Order Flame Gard Grease Filters", Flame Gard, obtained from website @ www.flamegard.com, (4 pages).
5"Takmodul med flytande tätning", Luftfilter, obtained from website www.luftfilter.com, Jun., 2001, (4 pages).
6"We prioritise expertise", Luftfilter, obtained from website @ www.luftfilter.com, Feb. 1999, (4 pgs.).
7Aerosol Science, Davies, C.N., 1966, 6 pages, Academic Press, London and New York.
8Aerosols; Science, Technology, and Industrial Applications of Airborne Particles, Liu, Benjamin Y.H., Pui, David Y.H., and Fissan, Heinz J., Sep. 17-21, 1984, 6 pages, Minneapolis, MN.
9CRC Handbook of Environmental Control, vol. I: Air Pollution; Richard G. Bond and Conrad P. Straub, 1972, 3 pages, CRC Press, Cleveland, OH.
10Desiccant Silica Gel, Silicagel.net, available by at least Oct. 7, 2003, 2 pages.
11Engineering and Design Adsorption Design Guide, Department of the Army, U.S. Army Corps of Engineers, Mar. 1, 2001, 99 pages, Design Guide No. 1110-1-2.
12Fuchs, N.A., The Mechanics of Aerosols, Karpov Institute of Physical Chemistry, Moscow, 1964, 4 pages, The MacMillan Company, NY.
13G. Elliott et al., "The Increasing Use of Ceramic Filters in Air Pollution Control Applications," Filtr. Sep. vol. 34, No. 4, pp. 331-335, 1997, Elsevier Science Ltd.
14Grease-X-Tractor (TM) Centrifugal Filtration, Grease Grabber (TM)-80 Two-Stage Filtration System, Greenheck, Aug. 2003, 18 pages.
15Greenheck Fan Corporation, "Overview," 6 pgs., marked as Oct. 27, 2000.
16Greenheck Promotional Materials for "Grease Grabber-80," 18 pgs., 2002.
17Greenheck, Grease Grabber Filter Style Kitchen Hood, Feb. 2005, 1 page, Greenheck Fan Corp.
18Greenheck, Various Promotional Materials, 10 pgs., (date unknown).
19Heating, Ventilating and Air-Conditioning, Systems and Equipment, 1996 ASHRAE Handbook, 5 pages, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta, GA.
20Heating, Ventilating, and Air-Conditioning, Applications, 1999 ASHRAE Handbook, 6 pages, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta, GA.
21Hinds, William C., Aerosol Technology; Properties, Behavior; and Measurement of Airborne Particles, 1999, 5 pages, John Wiley & Sons.
22International Search Report and Written Opinion for PCT-US2004-032311, Mar. 1, 2005, 9 pages.
23International Search Report for Application No. PCT/US2004/023377, 6 pages.
24J. Clark, "Commercial Kitchen Ventilation Design: What You need to Know," Engineered Systems, Jan. 29, 2003, 5 pages.
25J. Clark, "Commericial Kitchen Ventilation/IMC-2000," pp. 1-7 (date unknown).
26Jin, Do Won, et al., FTIR Study of Adsorption on Silica Gel for Organic Solvents Diluted in Supercritical Carbon Dioxide, Journal of Chemical Engineering of Japan, abstract, 1996, 1 page.
27Latest Development, Meigao Chemical Co., Ltd., copright date of 2002-2005, 3 pages.
28Livchak et a., "The Facts Mechanical Grease", American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Copyright 2003, Kitchen Ventilation / A Supplement to ASHRAE Journal Jun. 2003, (p. K14-K17, 4 pages).
29M. Sherer, "Clearing the Air," pp. 228-231, Foodservice Equipment Report, Jun. 2003.
30M. VandenBoom, Greenheck Product Presentation, 26 pgs., Oct. 23, 2002.
31N. Singh et al., "Process Design and Economic Analysis of A Ceramic Membrane System for Microfiltration of Corn Starch Hydrolysate," Journal of Food Engineering, vol. 38, No. 1, pp. 57-67, 1998, Elsevier Science Ltd.
32Scott, RPW, Liquid Chromatography, obtained from http:--www.chromatography-online.org-HPLC-Stationary-Phases-Silica-Gel-rs41.html, marked with 2002-2003 copyright date, 11 pages.
33Sell, Nancy J., Industrial Pollution Control, Issues and Techniques; 1981, 7 pages, Van Nostrand Reinhold Company.
34Silica Gel, Grace Davison, available at least as of Mar. 8, 2005, 2 pages.
35Standard Handbook for Mechanical Engineers, Baumeister, Theodore, Editor, Seventh Edition, 1967, 3 pages, McGraw-Hill, Inc.
36United Air Specialists, Inc., Promotional Materials for "Smog-Hog,", 4 pgs., 2001.
Classifications
U.S. Classification95/143, 55/DIG.36, 96/228, 96/231, 55/512, 96/108, 95/148, 95/276, 96/143, 55/525, 55/385.1, 55/523, 55/516, 96/151, 96/233, 95/281, 55/DIG.30
International ClassificationF01L1/344, B01D39/06, F01L1/34, B01D46/30, B01D53/04, B01D39/04
Cooperative ClassificationY10S55/30, Y10S55/36, B01D46/0028, B01D46/006, B01D39/04, B01D46/30
European ClassificationB01D46/30, B01D39/04, B01D46/00R20, B01D46/00F10
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